1. Field
This relates to a centrifugal blower and, more particularly, to a centrifugal blower having reduced noise and improved efficiency.
2. Background
An air conditioner may provide cooling or heating to a space using a refrigeration cycle including a compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger. Such an air conditioner may function as a cooler for cooling a space or as a heater for heating a space, or as an air conditioner for both cooling and heating a space.
An air conditioner may include an indoor unit provided, for example, at a ceiling of an indoor space to be heated/cooled so as to convey heated/cooled air into the indoor space, an outdoor unit installed outdoors, and a refrigerant pipe connecting the indoor unit and the outdoor unit to each other. The indoor unit may be installed in a main body, and a blower may draw indoor air through the indoor unit and then exhaust the air passing through the indoor unit into the indoor space. Such an air conditioner may instead be mounted on a wall of the space to be heated/cooled. In both of these arrangements, a heat exchanger may be disposed at the exhaust side of a centrifugal fan. A heat dissipation hole may be formed in a hub adjacent to a fan motor for cooling. However, such a heat dissipation hole may cause friction with air drawn into the unit, which generate noise and reduce efficiency of the fan.